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The Mass of Everything

As a complement to ""The Size of Everything"", here is the equivalent chart comparing the mass of everything that is known in space. Again the scale is logarithmic. The opaque range for each category indicates the mass range of objects that have actually been seen, while the gradient indicates either uncertainty, what may yet be found or what is theoretically possible. Large discrepancies are annotated in the table below. The data are mostly from Wikipedia, corroborated with the links given in the annotations. A conversion table for all used mass units is included in the chart.

The mass of an atom (as opposed to size) is dominated by the nucleus, so it is in good approximation proton mass * mass number. Can become much higher if the island of stability exists. Atomic Weights and Isotopic Compositions (NIST)

Molecule

3.3×10-27 – 2.4×10-27

1.87 GeV – 138 GeV

This refers only to those molecules so far found in space. The largest known molecules, i.e. DNA, measures in picogram, so there is much room for growth yet.

Dust

2.4×10-23 – 3.0×10-9

13.5 TeV – 3.0 µg

Dust mass is inferred from size and a density given as 1-3 g/cm3. See Interplanetary Dust (Wikipedia).

The dividing line between Meteoroids and Asteroids is assumed at ~10m, as discussed in "On the Definition of the Term Meteoroid". Mass limits are inferred from this and a density range of 1-9 g/cm3.

Asteroid

1.1×106 – 8.7×1020

10 kT – 1.45×10-4 m⊕

(See above) There is a general scarcity of mass estimates for the smallest objects up to moon size, so I extrapolated from the mass and density of the smallest object in each category for which I have found data: Asteroids: 1994 WR12; Comets: Halley; Moons: Euporie (Jupiter)

TNO

4.2×109 – 1.7×1022

4.2 MT – 2.83×10-3 m⊕

Lowest mass discovered so far is from a Hubble occultation discovery, but there is no reason to assume that TNOs don't have masses all the way down to dust.TNOs include the Kuiper belt, the Scattered disk, the Detached objects and the Oort Cloud. The discovered objects are mostly from the former three groups, with a few possible exceptions.

Comet

3.0×1013 – 1.0×1015

30 GT – 1,000 GT

(See 'Asteroid')

Moon

1.9×1012 – 1.5×1023

1.9 GT – 0.025 m⊕

(See 'Asteroid')

Dwarf Planet

9.5×1020 – 1.7×1022

1.58×10-4 m⊕ – 2.83×103 m⊕

This range is entirely determined by the definition of "Dwarf planet" and the objects so far classified as such.

Planet

3.3×1023 – 4.1×1028

0.055 m⊕ – 21.5 m♃

The limit between giant planets and brown dwarf is still a subject of debate. Here it is assumed to be somewhere between 13 and 21.5 Jupiter masses.

Brown Dwarf

2.5×1028 – 1.5×1029

13.0 m♃ – 80.0 m♃

(See above) This is the case likewise for the limit between brown and other dwarf stars: somewhere above 80 Jupiter masses or 0.1 solar masses.

Main Sequence Star

2.0×1029 – 8.0×1031

0.1 m☉ – 40.0 m☉

Star

8.0×1028 – 4.0×1032

0.04 m☉ – 200 m☉

The category Star here contains everything from Neutron Stars to Hypergiants, while the category above includes only regular stars of the main sequence.

(See 'Protoplanetary disk') Since Reflection Nebulae are basically a part of a Dark Nebula that is illuminated by a nearby star, and their bounds are not very well defined, they don't get an extra entry.